Start by washing and chopping the cabbage into bite-sized pieces after removing the core.
Heat olive oil in a large skillet over medium heat, then cook the thinly sliced onions until they become soft and translucent, about 5 minutes.
Add the minced garlic and cook for another minute until fragrant.
Stir in the chopped cabbage along with smoked paprika, salt, and black pepper; continue cooking while stirring occasionally for about 5 minutes.
Pour the vegetable broth, apple cider vinegar, and sugar into the pan, adding red pepper flakes if you want some heat, and mix everything together well.
Lower the heat to a gentle simmer, cover the skillet, and let the cabbage cook through for 20 to 25 minutes, stirring occasionally to prevent sticking.
Once the cabbage is tender and flavorful, remove it from heat and sprinkle chopped fresh parsley on top before serving.